ii. Sample Size Justification: The proposed study is a pilot trial designed to explore the relationship between inflammatory markers and the quality of recovery. To our knowledge this vital connection has never been investigated. Therefore, we cannot use commonly accepted methods of sample size calculations. Mahdy et al examined levels of IL-6, IL-10, and cortisol in patients undergoing urological surgery and treated with indomethacin versus placebo (12). A sample size of twenty three patients per group was sufficient to show a difference in cytokine levels. Tasdogan et al compared levels of interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-alpha in patients requiring postoperative ventilation after abdominal surgery and treated with dexmedetomidine versus propofol (18). A sample size of twenty patients per group was sufficient to demonstrate the difference in cytokine concentrations. Kim et al studied changes in cytokine levels in patients undergoing total abdominal hysterectomy and pretreated with clonidine (19). These investigators studied ten patients per group. The sample size was sufficient to demonstrate changes in IL-6 related to surgical stress. Therefore, we believe, that a sample size of 30 patients per group is an adequate sample to demonstrate the changes in level of inflammatory markers and explore the quality of recovery.